In a case that a mobile station and a relay station operate in a mode of quickly activating the relay station, the relay station is in an abnormal state when no signal is relayed. In addition, the relay station is wake up to be in an operating state by receiving a signal from any one of mobile stations within coverage of a signal of the relay station. In this case, a time sequence of the relay station is synchronized with that of the mobile station, and then the relay station relays signals from the mobile station. In this way, a process of activating a base station is not required, and therefore a call admission time is greatly reduced.
In the conventional technology, the mobile station can not know a current state of the relay station in advance after acquiring a transmission request and performing a transmission. In the case that the relay station is in the abnormal state currently, the relay station can not forward the currently transmitted signals. The abnormal state includes a case that the relay station is in a hibernation state, or a case that a distance between the mobile station and the relay station is so far as to be close to or exceed a signal coverage scope thereof. When the relay station is in the hibernation state, the mobile station can not know whether the relay station can be switched from the hibernation state to the operating state successfully, to forward the transmitted signal, in response to the signal transmitted to the relay station. In the case that the distance between the mobile station and the relay station is too far, a signal transmitted by the mobile station can not be received by the relay station normally. Thus, the mobile station can not make sure whether the transmitted signal can be received and forwarded by the relay station. Thus, the case that the mobile station transmits the signal unsuccessfully or the signal transmitted by the mobile station lost may happen always. In other word, one mobile station transmits a signal. However, the transmitted signal can not be received by other mobile stations with coverage of the same relay station. Thus, a high loss probability has a poor influence on user experience.